<!DOCTYPE html>
<html>
  <body>
    <svg width="100%" height="100%" mask="url(#m1)">
    </svg>
    <svg>
      <pattern id="p1">
        <mask id="m1">
          <polyline fill="url(#p1)" stroke="black" points="176,153 126,77 129,95 100,227"/>
        </mask>
      </pattern>
    </svg>
  </body>
</html>

